AMD uses DMCA to mitigate massive GPU source code leak

AMD has filed at least two DMCA notices against Github repos that carried "stolen" source code relating to AMD's Navi and Arden GPUs, the latter being the processor for the upcoming Xbox Series X. The person claiming responsibility for the leak informs TorrentFreak that if they doesn't get a buyer for the remainder of the code, they will dump the whole lot online.

I'd love to hear the backstory behind this hack. For a company like AMD, such a hack must've been an inside job, right? While I know I shouldn't be surprised anymore by just how lacking security can be at even the most prominent technology companies, I just can't imagine it being very easy to get your hands on this documentation and code without some form of inside help.